Package 'rbytecode'

Convert a bytecode data.frame to a text representation

Description

Convert a bytecode data.frame to a text representation

Usage

## S3 method for class 'bcdf'
as.character(x, incl_expr = FALSE, ...)

Arguments

x	bytecode data.frame produced by dis(), disq() and parse_code()
incl_expr	Include the stored expression? Default: FALSE
...	ignored

Examples

## Not run: 
as.character(disq(1 + 1))

## End(Not run)

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Compile bytecode assembly into an R bytecode object

Description

Compile bytecode assembly into an R bytecode object

Usage

asm(code, expr_default = quote(stop("[rbytecode]")))

Arguments

code	R bytecode assembly code as a single string
expr_default	The default expression stored with the bytecode. In general this should be a quoted 'call' object, and if you are running a standard modern version of R, then it will almost never get evaluated/called. Default: quote(stop("[rbytecode]")).

Value

bytecode object

Examples

## Not run: 
code <- "LDCONST 1\nLDCONST 2\nADD\nRETURN"
bc <- asm(code)
eval(bc) # 3

## End(Not run)

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Compile a bytecode data.frame to an executable R bytecode object

Description

Compile a bytecode data.frame to an executable R bytecode object

Usage

compile_bcdf(bcdf, expr_default = quote(stop("[rbytecode]")))

Arguments

bcdf	bytecode data.frame
expr_default	The default expression stored with the bytecode. In general this should be a quoted 'call' object, and if you are running a standard modern version of R, then it will almost never get evaluated/called. Default: quote(stop("[rbytecode]")).

Value

bytecode object

Examples

## Not run: 
code <- "LDCONST 1\nLDCONST 2\nADD\nRETURN"
bcdf <- parse_code(code)
bc   <- compile_bcdf(bcdf)
eval(bc)

## End(Not run)

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Disassemble R objects to a bytecode data.frame

Description

Disassemble R objects to a bytecode data.frame

Usage

dis(x, incl_expr = FALSE, depth = 0L, env = NULL)

Arguments

x	Possible inputs: language object, call object, compiled bytecode, functionquoted expression.
incl_expr	include the expression index in the output. Default: FALSE. This is an advanced feature
depth	internal variable tracking recursion depth. Not usually set by user.
env	environment for keeping track of labels. Not usually set by user.

Value

bytecode data.frame (bcdf)

Examples

## Not run: 
dis(quote(1 + x))
fc <- compiler::cmpfun(\(x) {2 * x + 1}) 
dis(fc)

## End(Not run)

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A wrapper for dis() which accepts unquoted expressions.

Description

A wrapper for dis() which accepts unquoted expressions.

Usage

disq(x, incl_expr = FALSE)

Arguments

x	unquoted expression
incl_expr	include the expression index in the output. Default: FALSE. This is an advanced feature

Examples

## Not run: 
disq(1 + 3)
dis(quote(1 + 3))

## End(Not run)

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Evaluate an expression with particular handling for SPECIAL functions

Description

R has many SPECIAL functions in the base R package that should be called in bytecode with CALLSPECIAL

Usage

eval_special(bc)

Arguments

bc	bytecode object to be evaluated

Details

But given it's a bit difficult to construct a CALLSPECIAL without just writing actual R code, there are some SPECIALs which can be handled by wrapping the special functions in a non-special wrapper.

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Information about all bytecode operators

Description

Information about all bytecode operators

Usage

ops

Format

An object of class list of length 129.

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Parse R bytecode assembly into a bytecode data.frame

Description

Parse R bytecode assembly into a bytecode data.frame

Usage

parse_code(code)

Arguments

code	Single string containing bytecode instructions

Value

bytecode data.frame (bcdf)

Examples

## Not run: 
code <- "LDCONST 1\nLDCONST 2\nADD\nRETURN"
parse_code(code)

## End(Not run)

---

Print a bytecode data.frame

Description

Print a bytecode data.frame

Usage

## S3 method for class 'bcdftxt'
print(x, ...)

Arguments

x	Character representation of a bytecode data.frame
...	arguments passed to cat()

Examples

## Not run: 
bcdf <- disq(1 + x)
txt  <- as.character(bcdf)
txt

## End(Not run)

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